cover of episode Recap: Red meat vs fake meat | Prof. Christopher Gardner

Recap: Red meat vs fake meat | Prof. Christopher Gardner

2025/3/11
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@Christopher Gardner教授 : 我进行了一项随机对照试验,比较了植物性肉类和红肉对健康的影响。试验中,参与者每天食用两份植物性肉类或红肉,持续八周。结果显示,食用植物性肉类的人群三甲基胺氧化物(TMAO)水平降低,低密度脂蛋白胆固醇下降,体重也减轻了大约一公斤。血压方面则没有显著差异。这项研究表明,就临床指标而言,植物性肉类替代品优于红肉,对于那些经常食用红肉的人群来说,这是一个健康的替代选择。 选择植物肉类替代品时,需要注意的是,要选择配料简单的产品,避免那些含有大量防腐剂、稳定剂、色素和乳化剂的超加工食品。建议消费者选择配料表中成分类似于家庭烹饪食材的产品。 总而言之,选择食物时,要考虑替代品。植物性肉类替代品相对于红肉而言,在改善健康指标方面有益,但仍需注意选择配料简单的产品。

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This chapter explores the composition and manufacturing process of meat alternatives, focusing on Beyond and Impossible brands. It highlights the use of pea and soy protein, the techniques to replicate the texture and taste of meat, and the manufacturers' focus on replicating the entire eating experience beyond just taste.
  • Beyond Meat uses pea protein, while Impossible Foods uses soy protein.
  • Manufacturers use extrusion to unfold and refold proteins, creating a meat-like texture.
  • The goal is to replicate the entire beef burger experience, including taste, smell, sound, and visual appearance.

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Hello and welcome to Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're talking about meat alternatives. It's well known that many of us should reduce our red meat intake, and chances are a lot of you already have. However, the cravings for that meaty flavor, the desire to sink your teeth into a nice juicy burger can still linger. It's no surprise then that supermarket shelves are now stocked with a growing variety of fake meat products.

However, are these meat alternatives actually any healthier? I'm joined by Professor Chris Gardner, whose randomized control trial compared the health effect of red meat against its plant-based counterparts. So help us understand what these new meat alternatives are, like what's in them. So the two ones that I'm most familiar with are Beyond and Impossible. I know there's many others. The idea is taking some kind of bean...

Beyond uses pea and Impossible uses soy. And instead of making a soy burger or a bean burger, extracting the protein in, and I don't know the exact process. I think sometimes it's called an extrusion. They're taking the proteins and through heat and pressure, they're unfolding and refolding them away in some ways. Like food engineers are doing this.

So that when you bite into it, it feels muscly and sinewy, like sinews of muscles. So it replicates the feel of this. So one is that mouth taste. Interestingly, I was years ago present at one of the design kitchens for these. And they said, you're welcome to have a tasting here. And they were all huddled together.

around the grill. And I said, I'm just over here at the table waiting to taste it. What are you guys all huddled around the grill for? I said, we're watching and we're smelling and we want to hear it when it hits the griddle. And we want to see the color when it's flipped. And we want to smell the aromatics coming off while it's cooking. And they were trying to replicate every aspect of the process. I said, aren't you just worried about the taste? No, no, no.

Our goal is actually to make the entire experience as close to a beef burger experience as we can. That's really interesting. I was stunned, actually, at taking all those different aspects into account. So I'd love to start to investigate then this question we started with, really, like, are these any good for you? And so from a sort of nutritional standpoint, how do these meat alternatives stack up

against your traditional meat. Well, you'd have to do a trial, but I'm going to back up and tell you why I did a trial. So picture this. I'm at home and three different times I saw a full page ad in the New York Times, full page with pictures of two products and a list of ingredients and

by the Consumer Freedom Choice Group, something like that, as like who paid for this advertisement, which as I understand it, I believe is funded by the Cattlemen's Association or something like that, but it's some more ambiguous, benign name. And basically the message in each one said, this is like dog food. Why would you eat this? It's like a full page ad to compare these new things to dog food, really? Yeah.

And so they were looking at these alternative meats and saying, like, there's all this stuff. This is basically dog food. And it has coconut fat, which is saturated. So it will raise your LDL cholesterol. It has high sodium. So it will raise your blood pressure. And it's ultra processed. So you will gain weight eating these. And I'm sorry, but a light bulb went off over my head. And I said, that is my superpower. I love it.

I design randomized trials to answer questions. This is an answerable question. Like I can't always tell you who lives or dies. That takes a long time to figure out. But if you're going to make claims about blood chemistry and weight, oh my God, that's what I do for a living. This would be such an easy trial to do. And so we designed a trial so that we could compare or we could test the effect of this. But the important thing is against what?

So we compared it against red meat because my question is always instead of what? So actually, I want to jump to the punchline at the end, which is we did this study and we published the results and they said, oh my God, you have some positive results here. Do you mean you want people to eat these instead of lentils and beans? I said, that's not the question. They got made to replace red meat. So the question is, are they better than red meat for these things? So

We designed a study that would compare the plant-based meats to these red meats and wrestled with a number of decisions. So by the time we get to the end, I want to make sure all the listeners agree or appreciate this is only one study. It's only one type of people. They're generally healthy people. Part of the struggle at first is you only get to pick one dose. So Jonathan, what dose would you pick? If you were trying to compare this

Let's talk about duration and dose. Would this be once a week? That probably wouldn't be enough to move the needle. Once a day, would that be enough to move the needle? How about all you get to eat is plant-based meat or red meat all day long, every day? That's too much. Where in the middle would you pick? Do you have any idea? I'm thinking twice a day.

Yeah, we did two servings a day. I was thinking about our interview with Walter Willard said he grew up eating meat breakfast, lunch and dinner. So I was thinking that's maybe a little less than that, but you would like to have it quite often. And so now, sorry, I'm going to put you on the spot again. Guess what proportion of calories...

That might be if you had two servings of the meat, not counting the buns that went on the burgers or anything like that, just the meat. Have any idea what proportion of calories that would be? I actually have no idea. It's 25% of calories. Okay, so quite a lot of your calories. But not the majority. Yeah. So 75% of what you're eating is what you normally eat. So in my mind, this is always, it's funny, I don't think people appreciate how much we struggle with that decision because once you make it, you're stuck with it.

So if it was too low, you might not find anything because it wasn't enough to see a signal be generated. And if it was too high, people will say, that's insane. No one could ever eat that much. What a stupid study. So you have to balance it that way.

And of course, it would be really nice to know who lived or died. So what would be the duration of this study? Let's see, how long could I get people to eat this? Well, our primary outcome in this study was listed on ct.gov. That's clinicaltrials.gov. When you have one of these studies, you have to pre-register it to say what you're looking at. We want to look at trimethylamine oxide, which let's talk about that later. But for now, TMAO.

That was the primary outcome, but also weight and blood pressure and cholesterol, because that's what a lot of the claims in the newspaper ads were highlighting as being problematic. So what did you find out? So the primary outcome, this trimethylamine oxide thing that I should explain, went down. And this is not a tough lift. So red meat has choline and carnitine in it, two molecules that the microbiome

converts to this thing called trimethylamine oxide, which is considered to be a heart disease risk factor that has inflammatory immune problem functions to it. And so the TMAO was lower on the plant-based meat. And that wasn't a huge surprise at all. The LDL cholesterol dropped more than I thought it would have, like 10 milligrams per deciliter in the plant-based meat relative to the animal meat.

The blood pressure was not different between the two groups. And actually, the most statistically significant finding was weight. The weight dropped by about a kilo or two pounds in the plant-based eaters. Even though we didn't have a caloric difference from checking all their diets and what they were eating, they were roughly the same calorie levels when we provided them. So

I was not expecting the weight to change, and I can't explain why it did. But a funny thing is why it was statistically significant, given that it's not really a clinically relevant amount. It's just a couple pounds. The reason it was statistically significant is almost every single person was one or two pounds lower on the plant-based meat for eight weeks than the other one. So when you're trying to get statistical significance, a big...

factor in here is how variable was the response. There was something positive that people were getting by switching out the red meat. TMAO was lower, LDL cholesterol was lower, weight was a surprise, and not a surprise that blood pressure wasn't any different. So three wins for plant-based over red meat if we're talking about health. Three things they were getting slammed for

And the press was, it's going to raise your cholesterol, raise your blood pressure, and you're going to be heavier. None of those were found. So Christopher, what's your verdict? Does that mean that it is healthy to swap from red meat to one of these? Yes, it is healthier. Like these are standard clinical measures that we have. And it won. And so that's my job, is to do these tests. So I'd love to sort of switch industries.

in a way to like practical advice based on this. You know, I think it's brilliant to understand that this is real and it looks like, you know, for people who are eating, you know, quite a lot of meat in their diet today, which, you know, many of us are, there is definitely a place for these meat alternatives. So if someone was thinking about switching from

from meat to meat alternatives, what should they look out for when they're buying these products? And are there any sort of red flags that would help you to think about it? Because I feel that there's more and more and more of these alternatives being advertised. Yeah. And right now, I'm actually chair of the American Heart Association's Nutrition Committee, and we're working on a statement about ultra-processed foods.

And as we go through this and try to explain it and take a position on it, there's really two components to those foods. And one is the physical processing. So here's the bean. I like soybean as an example. Soybean is the whole bean. Tempeh is pretty much the whole bean that's been fermented and stuck together. Soy milk is processed. Tofu comes from the soy milk, so it's further processed.

And then you've got soy protein isolate that you add. So you've taken the protein away from the whole bean. You can't even recognize the bean anymore, right? And then you're sort of hitting the ultra-processed. So one is the physical processing. But in the ultra-processed world, a big part of this is ingredients. It is preservatives, stabilizers, colorants, emulsifiers,

So I think what the consumer can do is look at this list of ingredients. So you'll find some of these plant-based meats have one or two of those additives or preservatives in it. But if they look, it's mostly just plain foods other than the pea protein or the soy protein that's extracted. I'm sure in other ones, there's a long list.

So we added red dye number three, and we added this preservative, and we added that emulsifier, and we added this other thing. And so that's their challenge. So I would suggest they look to see the thing that has what Marian Nestle, who's a very well-known nutrition scientist in the U.S., she says...

Avoiding ultra-processed foods mean you should try to pick things where you could find the ingredients in the store to make it at home. You're saying like you're looking on the back of the pack and you might see one which basically just looks like things in your kitchen with maybe the addition of your...

or pea protein that feels to you a lot better than one that has lots of different preservatives and emulsifiers. And that's sort of what you should be looking out for. - And then you find one that has none and it's a lentil black bean burger and you bring it home and the meat eater in your family says, "I'm not eating that. "That doesn't look or taste like the burger that I wanted."

Oh, I'll have this other one. That looks and tastes like it. Oh, no way you fooled me. It's not. So Christopher, just to wrap up, what's your one key piece of advice that you'd want our listeners to walk away with from this episode? Yep. Eat whole foods first, but along the way to that path, consider instead of what. So are these plant-based alternative meats good or bad for you?

It needs to be in terms of instead of what? And if you are a regular American eating a lot of the meat that's available in the US and you wanted to focus on clinical measures, those plant-based alternative meats in our study, which is only one, had better health outcomes. That's it for today's recap. If you want to continue your health journey with Zoe, why not try our membership? Zoe is your daily coach to better health for life.

Click the link in the show notes to get started today. And don't forget to follow Zoe Science and Nutrition in your favorite podcast player so you never miss an episode. See you next time.